The invention relates to a climbing device comprising a rope anchored by one of its ends to a support and at least one first engagement arrangement which can be locked securely on the rope in such a manner that the device is displaceable in the direction towards the anchored end of the rope under the action of a climbing force and in locking engagement with the rope when the climbing force stops.
Devices of this type are used together with safety harnesses especially as personal fall-prevention equipment during climbing of all types, whether mountain climbing or climbing associated with buildings or structures of various types, for example for generating hydroelectric power, and in inter alia the performance of maintenance and rescue work. In the latter type of work, the load usually comprises at least one person as well as the equipment necessary for the work, which may be heavy to lift by means of muscular strength alone.
Horizontal movement of a load, for example a person, may also come into consideration in those situations where it is necessary for the load to be continuously secured in an optional position between an initial position and a final position. Examples of situations in which such horizontal load movement may be relevant are where violent storms (hurricanes etc.) advance across land and sea.
For various reasons, it may sometimes be advantageous to be able to xe2x80x9cwinch homexe2x80x9d a load or a person in distress by means of a winch, which is carried out, for example in the case of a helicopter rescue, by means of a winch mounted in the helicopter, which is operated by a winchman. A surface rescuer is winched down to the person in distress by the winchman who then winches up both the person in distress and the surface rescuer separately or together. This is demanding in terms of both personnel and resources but of course well-justified for the purpose of saving life.
For certain purposes, it is advantageous or even a vital necessity to be able to maintain the same high level of safety in simpler situations which are less demanding in terms of personnel and resources. For example, during the maintenance of turbines of hydroelectric power stations, a maintenance person is usually winched down by a winchman through a manhole to ducts and spaces which are filled with water during operation, can be kept free of water for maintenance work only for relatively short periods of time by means of hatches that are not completely leakproof, and are shielded from radio waves. On account of the risk of water penetration and also the restricted access to air, the maintenance person must therefore as a rule carry with him oxygen equipment, and communication must be maintained by signs, loud shouts or via a wire or cable link. This is because, when the water level begins to become alarmingly high, the maintenance person is dependent upon the attentiveness of the winchman for being winched up.
The object of the invention is therefore to provide an improved climbing device of the type indicated in the introduction, which allows winching-home according to established safety margins (on the initiative of the maintenance person) to be performed in a simpler, more reliable and more efficient manner than previously, independently of communication systems and without the assistance of a separate winchman.
According to the invention, this is achieved by virtue of the fact that the device is equipped with at least one drivable second engagement arrangement which is arranged so as to act on the free end of the rope between the locking engagement of the first engagement arrangement with the rope and a load connected to the device, for example a user equipped with a safety harness, in order to produce the climbing force and move the locking engagement towards the anchored end of the rope.
Further features and advantageous developments and improvements of the invention emerge from the measures indicated in the dependent patent claims.